Chain of combined terminal and support members for electrical elements



Feb. 3, 1959 T. R. HARRIS 2,871,551

- CHAIN OF COMBINED TERMINAL AND SUPPORT MEMBERS FOR ELECTRICAL ELEMENTS2' Sheets-Sheet 1 Filed Oct. 19, 1955 PRIOR IIFT INVENTOR.Tho/720621901715,

Feb. 3, 1959 CHAIN 0F COMBINED '1 Filed Oct. J9. 1955 T R. HARRIS 7ERMINAL AND SUPPORT MEMBERS FOR ELECTRICAL ELEMENTS 2 Sheets-Sheet 2MING 1'! I' Q I HII INVENTOR. T/zams E [far/ 6 United States PatentCHAIN OF COMBINED TERMINAL AND SUPPORT I MEMBERS FOR ELECTRICAL ELEMENTSThomas R. Harris, Arlington Heights, 111., assignor to Malco Tool & Mfg.Co., Chicago, 111., a partnership Application October 19, 1955, SerialNo. 541,372

2 Claims. (Cl. 29-1935) This invention relates to a combined terminaland support member for electrical elements and more particularly to aterminal capable of being fabricated in the form of a chain suitable forfeeding into automatic machines and which is particularly adapted foruse with printed circuit boards.

It is, therefore, an object of this invention to provide a combinedterminal and support member for electrical elements of the characterdescribed which is particularly useful in the automatic assembly ofelectronic circuit components. It is a further object to provide aterminal which is particularly useful for installation in printedcircuit boards, the terminal being adapted to be disposed in such boardsaccurately and positively and also being adapted to be readily securedpermanently in position in such boards.

In addition, it is an object to provide terminals fabricated in the formof a chain and disposed substantially in fixed spaced relation to eachother while they are in this chain form. Still another object is toprovide a chain of terminals of the character described in which theterminals are so disposed and so fabricated that they serve as atemporary support for the electrical elements to which they aresubsequently permanently secured. Yet another object is to provideterminals of the character described which are self aligning.

Further objects and advantages of this invention will become evident asthe description proceeds and from an examination of the accompanyingdrawings which illustrates one embodiment of the invention and in whichsimilar numerals refer to similar parts through the several views.

. In the accompanying drawings:

Figure l is a plan view of one form of prior art terminal shown inassociation with a disc capacitor.

Figure 2 is a plan view of a fragmentary portion of a printed circuitboard, two' terminal receiving openings being shown with two forms ofprior art terminals disposed therein and shown in cross section.

Figure 3 is a view in elevation of a fragmentary portion of a chain ofcombined terminal and support members incorporating one form of thepresent invention.

Figure 4 is an enlarged-side view of av fragmentary portion of one ofthe terminals shown in Figure 3 after having been removed from the chainand installed in' a printed circuit board, the board beingshown invertical section.

Figure 5 is a view in side elevation of one of the terminals shown inFigure 3, the view being taken along the line 5-5 of Figure 3.

Figure 5a is a view in side elevation of another of the terminals shownin Figure 3, the view being taken along the line 5a-5a.

Figure 6 is an end view in elevation of two of the terminals shown inFigure 3.

Figure 7 is a plan view of a fragmentary portion of a chain of terminalshaving an alternative form of construction.

I of the terminals shown in Figure 8, the view being taken along theline 10-10.

Figure 11 is a view in horizontal section of one of the terminals shownin Figure 8, the view being taken along the line 1111 of Figure 8.

Referring now to Figures 1 and 2 of the drawing, one form of combinedterminal and support member of the prior art is shown in Figure 1. Thetwo terminals 10 and 12 are in the form of wires of circular crosssection. They are each secured by soldering in association with ametallic disc 14 disposed on opposite sides of an insulating disc 16 ofdielectric material. The entire disc assembly is normally coated with asuitable insulating covering material, indicated by the dotted line 18,after the supporting members 10 and 12 have been secured to the discs 14thereto. The finished assembly forms a miniature capacitor which can bemounted in an electronic circuit through the wires 16 and 12, in anysuitable manner.

In Figure 2 a fragmentary portion of a printed circuit board is shown,the two holes 20 and 22 in the board 24 having associated therewithstrips 26 and 28 of electrically conducting material, as is conventionalpractice in the fabrication of such printed circuits. The manner inwhich the wire terminals 10 and 12 would be likely to be received withinone of these circular openings is illustrated in the opening 22 inFigure 2. The wire 30 is shown in cross section in the center thereof,the diameter of the opening 22 being substantially larger than thediameter of the wire 30. Obviously, unless the wire 30 is of a diametervery slightly smaller than the diameter of the hole 22, it will be verydifiicult to secure an electrical element in association with theprinted circuit board by inserting terminals such as the terminals 10and 12 in the holes 20 and 22. Not only is there a problem of adequatetemporary support for the electrical element being so mounted but thereis also a problem of obtaining a satisfactory permanent electricalconnection between the wire terminal and the printed circuit which, inthe case of the hole 22, is the ribbon of electrically conductingmaterial 28 which circumscribes the hole 22.

A flattened form of support member 32, also common to the prior art, isshown in association with the other opening 20 in the printed circuitboard 24 shown in Figure 2. This type of support member may have atapered form so that it will seat in the opening 24], after it has beeninserted a sufiicient distance. Here the problem of adequate support ispartially answered but again there is a problem of satisfactoryconnection between the printed circuit portion 26 and the terminal 32.The only parts oi the terminal 32 which are in close association withthe portion 26 of the printed circuit which circumscribes the hole 20are the two lateral edges 34 and 36. It is customary to simultaneouslysolder all of the supporting and terminal elements to the printedcircuit by bringing the surface of the board having the circuit thereoninto association with the surface of a bath of molten solder. Theconnection between the supporting and terminal elements and the printedcircuit is thereby made by molten solder being deposited on and betweenthose two elements, and the subsequent solidification thereof. In thecase of the support element 30 shown in Figure 2, such a deposit wouldprobably not take place because of the relatively large annular spacebetween the support element 30 and the printed circuit portion 28. Inthe case of the support element 32, a deposit of solder interconnectingthe element 32 and the portion 26 of the printed circuit would be madeat the two lateral edges 34 and 36, but there would not be sufficientcapillary action to entirely till the space between the edge of the hole20 and the flat side of the element 32 with molten solder and theresultant joint would not be satisfactory in many in stances.

In Figure 3 an improved form of combined terminal and support member isdisclosed which overcomes this difficulty of possible defectiveconnection between the terminal and the printed circuit. The terminals38 and 40 shown therein are preferably formed integrally from a strip ofconductive material such as a suitable metal. In the forming operationone end 42 of each terminal is left secured to a tongue member 44 whichis an integral part of the feeding strip 46. This strip may be providedwith suitable perforations 48 to aid in the feeding thereof to anautomatic terminal dispensing and setting machine.

The end 42 of each terminal is in the form of a substantially tubularbase portion 50 best shown in Figure 4. This base portion may be formedof two sides 52 and 54 rolled to form a generally tubular section with alongitudinal gap 56 between the upper edges of the two sides 52 and 54.The upper end 58 of the base portion 50 in addition is preferably flaredoutwardly, While the end 42 is preferably tapered inwardly, thus givingan area of increased diameter at the end 58 and an area of reduceddiameter at the end 42. This construction of the base portion permitsthe terminal to be readily inserted in a suitable opening such as theopening 60 in the printed circuit board 62 shown in Figure 4. When soinserted, the area of enlarged diameter 58 will be brought into abutmentwith the upper edge 64 of the opening 60 and it will, therefore, providea means of aligning the terminal with respect to the opening 60 and willcause it to stand upright in the board 62. The main body of the baseportion 50 will, therefore, be held substantially in the position shownin Figure 4 by the flared upper end I i The alignment of the terminal inthis position will permit the forming of a satisfactory soldered joint66 between the main body of the base portion 50 and the portion of theprinted circuit 68 which is in association with the hole 60. Because ofthe relatively narrow annular opening between the terminal and the hole60, the solder, through capillary action, will flow and solidify to forman annular joint completely around the pin or terminal, contrary to thecondition which is likely to result in connection with pins of the formshown in Figure 2.

As shown in Figures 5, a and 6, it may be desirable to have the shankportion 70, Fig. 5a, of one of each pair of terminals otlset. This willpermit the insertion of a disc such as that represented in Figure 1between a pair of adjacent terminals, and each terminal will be incontact with the opposite face of a disc capacitor as shown in Figure 1.It may also be desirable to provide the shank portions with a rib 72,adding strength and rigidity to the terminal so that it will form a firmsupport for the electrical element associated therewith. The terminalmay preferably be further strengthened by flaring the base of the shankportion on both sides thereof, as best shown at 74 in Figure 5, so as toprovide an area of greater strength between the base portion 50 and theshank portion 70.

j The strip 46 can be utilized to chain feed the terminals intoautomatic machinery for severing, feeding and applying them to printedcircuit boards. The terminals are preferably severed at the end 42 sothat the tongue 44 is removed clearly from the terminal.

An alternative form of terminal pin incorporating the invention is shownin Figure 7. In this alternative form the upper end 78 of the shankportion is in the form of a flat, plate-like member having an opening 80therein to assist in securing the end 78 to the electrical element to besupported. A strengthening rib 82 is provided in the central portion ofthe sharik similar to the rib 72 pre viously described. The shankmembers 76 are also connected together by a narrow ribbon of material 84forming an electrical connection therebetween. Although three adjacentterminals are shown connected together in Figure 7, it is obvious thatadjacent pairs of terminals could be connected by a connecting ribbon84, or the entire chain of terminals could be so connected. Theparticular pattern for this connecting strip 84 will depend, of course,upon the use to be made of the terminals. Where it is desirable to haveseveral terminals interconnected, the strip 84 can be utilized for thispurpose. It would also, of course, be possible to have all of the terminals so connected and to sever portions of the strip 84, as desired,at the same time that the terminals are severed from the tongue 44connecting to them to the strip 46. The offsetting of the shanks of theterminals can also be coordinated with the pattern of the connectingstrip 84 since normally terminals on opposite sides of the supportedelectrical element would not be so connected together.

Figure 8 illustrates still another form of terminal embodying theinvention, this particular form being particularly adapted for use inthe manufacture of disc capacitors, any like flat elements such asprinted resistors or resistor-capacitor combinations. As shown in Figure8, pairs of terminals 86 and 88 are formed so that their upperextremities 9t) and 92 overlap. In addition, the upper ends 9i) and Ware brought into close association so that a disc capacitor element ofthe type shown in Figure 1, for example can be frictionally heldtherebetween. This characteristic is best shown in Figure 9 where theshank 94 of the terminal 88 is shown displaced inwardly toward the shank96 of the terminal 86. In addition, as shown in Figure 8, the majorportion of the shanks 94 and 96 are angularly disposed with respect tothe bases of the terminals so that they angle inwardly toward eachother. The upper extremities 90 and 92 are likewise angularly disposedwith respect to the shanks 94 and 96 so that they are substantiallyhorizontal and overlap each other to a substantial degree. Astrengthening rib 98 may be provided in the shank 94 and a strengtheningrib 100 in the shank 96 as best shown in cross section in Figures 10 and11. The base portion of the terminals shown in Figure 8 is substantiallythe same as that previously described in connection with the form shownin Figures 3 and 7.

As previously mentioned, a longitudinal slit 56 is provided in the baseportion of all the forms of terminal just described. This provides aspring action in the base portion which facilitates the proper seatingof the terminal. Likewise, the fact that the terminals are maintained inproper alignment by being integrally formed with the strip 46 makes itmuch easier to carry out the proper positioning and temporary support ofany electrical element to be subsequently secured to and permanentlysupported thereby. A pair of terminals of the form shown in Figure 8,for example, forms a holding fixture for the electrical element to besupported which obviously eliminates considerable handling of individualparts and greatly simplifies the assembling operation when an electricalelement is to be secured thereto by solder:

and although specific terms are employed, they are used in a generic anddescriptive sense only and not for purposes of limitation. Changes inform and in the proportion of parts, as well as the substitution ofequivalents are contemplated, as circumstances may suggest or renderexpedient, without departing from the spirit or scope of this inventionas further defined in the following claims.

What is claimed is:

1. A chain of combined terminal and support members for electricalelements comprising a perforated strip of electrically conductingmaterial, a plurality of combined terminal and support members formedintegrally with and extending laterally from said strip in spacedrelation to each other, each said terminal and support member includingan elongated fiat shank portion having a longitudinally disposedstrengthening rib formed therein and extending substantially the entirelength of the shank portion, the shank portions of each pair of adjacentterminals being disposed in ofiset parallel planes and forming atemporary holding fixture for an electrical element to be sunbsequentlypermanently secured thereto, an integral substantially tubular baseportion, said base portion being outwardly fiared at its end connectedwith said shank portion to provide an end diameter greater than thewidth of said shank portion and to provide a conical area of contactadapted to be seated in a circular opening in a printed circuit board,the opposite end of said base portion being inwardly tapered toward theouter extremity thereof to form a tapered nose substantially smaller indiameter than the diameter of said circular opening, said base portionbeing longitudinally split to form a longitudinal slot of substantialwidth to allow resilient contraction of the circumference of the baseportion when inserted into said circular opening, and a severable tongueintegrally connecting the base portion of each of said terminal andsupport members to said strip adjacent said tapered nose.

2. A chain of combined terminal and support members for electricalelements comprising a perforated strip of electrically conductingmaterial, a plurality of combined terminal and support members formedintegrally with and extending laterally from said strip in spacedrelation to each other, each said terminal and support nienn berincluding an elongated fiat shank portion having a longitudinallydisposed strengthening rib formed therein and extending substantiallythe entire length of the shank portion, an integral substantiallytubular base portion, said base portion being outwardly flared at itsend con-- nected with said shank portion to provide an end diametergreater than the width of said shank portion and to pro vide a conicalarea of contact adapted to be seated in a circular opening in a printedcircuit board, the shank portions of each pair of adjacent terminalsbeing provided with parts angularly disposed with respect to said baseportions so that said parts of each adjacent pair of shank portionsoverlap to form a holding fixture for an electrical element, theopposite end of said base portion being inwardly tapered toward theouter extremity thereof to form a tapered nose substantially smaller indiameter than the diameter of said circular opening, said base portionbeing longitudinally split to form a longitudinal slot of substantialwidth to allow resilient contraction of the circumference of the baseportion when inserted into said circular opening, and a severable tongueintegrally connecting the base portion of each of said terminal andsupport members to said strip adjacent said tapered nose.

References Cited in the file of this patent UNITED STATES PATENTS OTHERREFERENCES Am-P Electrical Manufacturing, August 1953, page 143.

